Question

what is melting point and boiling point

Answer 1

The constant temperature at which a solid becomes liquid upon absorption of heat under normal pressure is called the melting point of that solid. The constant temperature at which a liquid changes to vapour under normal atmosphere pressure is called the boiling point of that liquid.

Answer 2

The boiling point is the temperature at which a material changes from a liquid to a gas (boils) while the melting point is the temperature at which a material changes from a solid to a liquid (melts). Keep in mind that a material's melting point is the same as its freezing point.